JPH02256548A - Belt winding device of safety belt- restriction system - Google Patents

Abstract

PURPOSE: To quietly carry out the change of belt tensile force by arranging a spiral auxiliary spring on a ratchet rotatably installed between a belt reel and a winding spring and providing a brake system to delay the rotation of the ratchet with the auxiliary spring as a driving source. CONSTITUTION: An inner end of a spiral auxiliary spring 22 is engaged with an outer periphery of a driving sleeve 18 on which a belt reel 12 rotatably installed on a housing 10 of a belt winder is fixed, and an outer end of this auxiliary spring 22 is connected to a ratchet 24 rotatably installed, on a pin 28 integrated with a housing cap 30. A click (not shown in the drawing) actuated by an electromagnet 36 is engaged and disengaged with a stop tooth 32 of the ratchet 24. Additionally, an inner end of a spiral winding spring 38 is engaged with an outer periphery of a hub 26 of the ratchet 24, and its outer end is fixed on the cap 30. Thereafter, a plural number of engagement members 40 with the auxiliary spring 22 as a driving source are pivotally installed 42 on one side surface of this ratchet 24, made to cooperate with a friction disc 44 installed on the driving sleeve 18 and made to function as a brake system.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention provides a belt winder for a safety belt restraint system for an automobile, which includes a salator member fixed to a housing;
The present invention relates to a belt winder having a winding spring that operates between a belt winding reel and a belt winding reel.

There are many known belt winders of this type.

To increase belt wearing rates, it is desirable to minimize the pressure exerted on the occupant by the fastening belt. This is primarily achieved by making the winding spring relatively weak. However, the take-up spring must be strong enough to completely and reliably take up the belt when it is loosened, thus limiting its ability to reduce the tension in a tightened belt.

Various proposals have been made to reduce the force of the winder or winding spring after the safety belt has been donned. For example, after a decision has been made to tighten the belt according to certain criteria, an auxiliary spring can be provided to apply an opposite force to the winding spring. Note that a force reducing device can be selectively inserted between the take-up spring and the belt reel. However, the mechanism required for this is complex;
And expensive.

(Problems to be Solved by the Invention) The present invention is a belt winder of the type mentioned in the preamble, and has a simple device for reducing the belt tension after the safety belt has been fastened. The problem relates to the use of a belt winder in which the changeover between reduction and non-reduction occurs silently and without shocks.

(Means for Solving the Problem) According to the present invention, this problem can be solved by providing a belt winder as described in the preface, which is rotatably mounted between a winding spring and a belt reel, and which is rotatably mounted between a winding spring and a belt reel. A ratchet wheel drivingly connected to one end and a helical auxiliary spring weaker than the take-up spring are operatively arranged such that the auxiliary spring can further operate between the ratchet wheel and the belt reel. wherein the ratchet wheel cooperates with a pawl for locking or releasing rotational movement thereof according to a control criterion, and a braking device is associated with the ratchet wheel, the braking device retarding rotation of the ratchet wheel relative to the housing. , and the function of the braking device is controlled by the auxiliary spring, and is biased at least when the auxiliary spring is loosened, and is deenergized when the auxiliary spring is tensioned. solved by.

In the belt retractor according to the invention, the take-up spring and the auxiliary spring are functionally located in series between the belt retractor housing and the belt reel, as long as the safety belt is not fastened. The fastening of the safety belt is determined, for example, by a switch in the belt lock which is actuated by an insert tongue. Since the take-up spring is made stronger than the auxiliary spring, the auxiliary spring is fully tensioned by the take-up spring, which extends to the "locked" position, and the force generated by the take-up spring is reduced. Acts on the belt reel without any problems. However, as soon as the safety belt is fastened, the ratchet wheel is held non-rotationally by a pawl driven by an electromagnet in its teeth, so that only a weak auxiliary spring operates between the housing and the belt reel. , thus the tension on the belt is reduced and the wearing comfort is increased.

When the safety belt is loosened, the pawl releases the ratchet wheel again, so that the take-up spring is operated with a non-reducing force between the housing and the belt reel, and the auxiliary spring is tensioned.

When the aforementioned operations are carried out, the braking device is activated until the auxiliary spring is fully tensioned, so that the reduced and non-reduced states of the belt tension can pass silently without impact. This brake prevents rotation of the ratchet wheel due to the force of the take-up spring until the auxiliary spring is fully tensioned, i.e. extended to the "locked" position. In this way, a rapid acceleration of the ratchet wheel due to the action of the winding spring is prevented, and the rotation of the ratchet wheel is then suddenly retarded when the auxiliary spring is subsequently tensioned and its windings are brought into close proximity to each other. shocks and loud noises are thereby prevented.

Therefore, excellent "comfort" can be obtained.

In a preferred embodiment of the belt winder according to the invention, the braking device is responsive to the outer diameter of the auxiliary spring, which by means of its outer diameter activates the mechanism governing the functioning of the braking device. The mechanism preferably has at least one engagement member, which element is mounted on the ratchet wheel and whose outer periphery presses against the ratchet wheel in the at least partially tensioned state of the auxiliary spring. , the ratchet wheel is moved by the force of an auxiliary spring into an operative position, in which position the engagement member frictionally engages a member fixed to the housing. The outer diameter of the auxiliary spring is a simple criterion for determining whether the auxiliary spring is tensioned or relaxed. When the auxiliary spring is fully tensioned, i.e. when its windings are close to each other, the engagement member separates from the outer circumference of the auxiliary spring and automatically returns to the inoperative position, and this position It is very advantageous that the frictional connection with the member fixed to the housing is released and that the braking device is therefore not actuated. In addition to the switching between reducing and non-reducing the belt tension, the winder according to the invention thus performs another function, namely the transition between reducing and non-reducing the belt tension, silently and without any impact. It has the ability to selectively activate such braking devices, but does not require additional components to control this function.

To keep the brake device activated until the auxiliary spring is fully or nearly fully tensioned, the auxiliary spring is strengthened at its outermost turn(s) and its outer periphery is engaged. The turns within said portion are allowed to contract before being separated from the member.

Other advantages and features of the invention will become apparent from the exemplary embodiments described below with reference to the accompanying drawings, in which: FIG.

(Embodiment) A belt reel 12 is rotatably mounted in a housing 10 of a belt winder. Via a mechanism housed in the intermediate chamber 14, a mechanism which will not be described here as it is not necessary for an understanding of the invention, the belt is connected to the drive sleeve 18 which is rotatably mounted in the housing. A reel 12 is non-rotatably connected. The drive sleeve 18 is rigidly connected to a member 20 that is non-rotatably connected to the belt reel 12. The inner end of the helical auxiliary spring 22 engages the outer periphery of the drive sleeve 18, and the turns of the spring coaxially surround the drive sleeve 18. The outer end of the auxiliary spring 22 is connected to a ratchet wheel 24, which is rotatably mounted by the hub 16 on a pin 28 formed integrally with the housing cap 30. The ratchet wheel 24 has pawl teeth 3 uniformly distributed around its outer circumference.
It has 2. This retaining tooth 32 cooperates with a pawl 34 rotatably mounted on the housing, and this pawl works with the electromagnet 3.
6. The electromagnet 36 is further controlled by a switch located within the belt lock (not shown) to be activated by inserting a tongue into the belt lock.

A helical winding spring 38 is attached to the outer periphery of the hub 26 of the ratchet wheel 24.
The inner ends of the two are engaged. The outer end of the take-up spring 38 is fixed to the housing cap 30. The take-up spring 38 and the auxiliary spring 22 are thus operatively connected in series between the housing cap 30 and the belt reel 12 via the ratchet wheel 24, so long as the ratchet wheel 24 is free to rotate. However, the take-up spring 38 is not the same as the auxiliary spring 22.
It is made considerably stronger and applies a force to the auxiliary spring 22 until the windings of the auxiliary spring 22 come close to each other. In this state, the unreduced force of the take-up spring 38 acts between the housing and the belt reel 12.

When the electromagnet 36 is actuated by operating a switch in the belt lock, its armature pivots the tip of the pawl 34 into the passage of the pawl 32 of the ratchet wheel 24, causing the ratchet wheel 2 to pivot.
Prevent rotation of 4. Since the ratchet wheel 24 is now fixed to the housing, only the force of the auxiliary spring 22 acts between the housing and the belt reel 12, i.e. a considerably reduced force compared to the force of the take-up spring 38. The tensile forces in the belt are therefore correspondingly reduced.

When loosening the safety belt, use the electrode stone 36 to tighten the pawl 3.
4 is released and removed from the path of the pawl 32 by the action of the return spring, allowing the ratchet wheel 24 to rotate again. The take-up spring 38 then causes the ratchet wheel 24 to rotate, thereby tensioning the auxiliary spring 22 until its turns are brought into close proximity to each other. As soon as this condition is reached, the unreduced force of the take-up spring 38 again acts between the belt reel and the housing.

In order to ensure that the transition between the reduced tension and the unreduced tension of the belt occurs slowly, that is, without any impact and silently, a braking device is provided. The ratchet wheel 24 is prevented from rotating until the auxiliary spring 22 is fully tensioned. When the auxiliary spring 22 is fully tensioned, excessive acceleration of the ratchet wheel 24 and a corresponding sudden deceleration can be avoided.

In the embodiment shown, the braking device consists of a plurality of engagement members, which are uniformly distributed on the side of the ratchet wheel 24 facing the belt reel 12 and mounted on the ratchet wheel 24. . One of these engagement members 40 is shown in FIG. This engagement member 40 forms a two-armed lever, with a wire ring 4 held on the ratchet wheel 24 of the lever.
2 is pivotally mounted on this ratchet wheel 24. The substantially axial first arm of the engagement member 40 is in contact with the outer periphery of the auxiliary spring 22 unless the auxiliary spring 22 is tensioned. The generally radial second arm of the engagement member 40 forms an engagement surface that faces the belt reel 12 and that engages a friction disc rotatably mounted on the drive sleeve 18 and a drive drive surface. work together. The interdiscs have a friction surface on the side remote from the engagement member 40, which friction surface frictionally engages an opposing friction surface 46 on the wall 48 of the housing. In response to pressure applied from the outer periphery of the auxiliary spring 22, the engaging member 4
0 pivots approximately axially with its radial arms relative to the friction discs and presses the friction surfaces between the friction discs and the wall 48 of the housing against each other. FIG. 2 shows the operating state of this braking device.

The operating state of the brake device is maintained until the auxiliary spring 22 is fully or almost completely tensioned. For this purpose, the auxiliary spring 22 is reinforced at its outer periphery or at its outer turn(s). This can be done simply by inserting a leaf spring between the two windings of the auxiliary spring 22 in said section. The braking device thus remains active until the transition between decreasing and non-reducing belt tension is completed, ensuring that the transition occurs quietly and without shocks.

Although the description is omitted, in another embodiment, the auxiliary spring 22
When relaxed, the engagement member is pressed radially outwards directly by the pressure of the auxiliary spring and engages, for example by its outer periphery, a friction surface fixed to the housing surrounding the ratchet wheel 24. be made to do.

[Brief explanation of drawings]

1 is a schematic side view of an embodiment of a belt winder according to the invention, and FIG. 2 is a sectional view of said belt winder taken along line II--II in FIG. 10...Housing, 12...Belt reel, 22
... Auxiliary spring, 24 ... Pawl wheel, 32 ... Teeth, 3
4... Pawl, 38... Winding spring, 40... Engaging member, wing... Friction surface, 46... Friction disk, 48...
·wall.

Claims (12)

[Claims] (1) A belt winder for an automobile safety belt restraint system, which includes a member fixed to a housing and a belt reel for winding the belt,
A ratchet wheel (24) is functionally rotatably mounted between the take-up spring (38) and the belt reel (12), and one end of the take-up spring (38) is drivingly connected to the ratchet wheel. , and a helical auxiliary spring (22) which is weaker than the winding spring is disposed, and this auxiliary spring (22) is further connected to the ratchet wheel (24).
and a belt reel (12), said ratchet wheel (24) cooperating with a pawl (34),
The pawl is adapted to lock or release the rotary movement of the ratchet wheel (24) according to the control criteria;
4) is provided with a braking device (40, 44, 46) for retarding the rotation of the ratchet wheel relative to the housing (10), the function of which is controlled by an auxiliary spring (22), at least Belt winder, characterized in that it is activated when the spring (22) is relaxed and is stationary when the auxiliary spring (22) is tensioned. (2) The braking device (40, 44, 46) is connected to the auxiliary spring (22
2. The belt retractor of claim 1, wherein the belt retractor is adapted to be responsive to the outer diameter of the belt. 3. A belt winder as claimed in claim 2, characterized in that the auxiliary spring (22) operates, by its outer circumference, a mechanism (40) for controlling the function of the braking device. (4) the mechanism has at least one engagement member (40) mounted on the ratchet wheel (24);
) is in at least its incompletely tensioned state, the outer periphery of the auxiliary spring contacts the engagement member, and the engagement member is moved into the activated position by the force of the auxiliary spring (22);
4. A belt winder according to claim 3, wherein in this position said engagement member (40) is adapted to frictionally engage a member (48) fixed to the housing. (5) When the auxiliary spring (22) is fully tensioned, the engaging member (40) is removed from the outer periphery of the auxiliary spring and automatically moves to the non-operating position, and is fixed to the housing in this position. 5. A belt winder as claimed in claim 4, characterized in that the belt winder is not frictionally connected to the attached member (48). (6) The belt winder according to claim 4 or 5, wherein the engaging member (40) is pushed in the axial direction toward the operating position by pressure applied from the outer periphery of the auxiliary spring (22). (7) the engagement member (40) is formed as a two-arm lever;
The lever is pivotally mounted on the ratchet wheel (24) and is driven by an auxiliary spring (24) by means of its first arm extending substantially axially.
22) and has an engagement surface on its second arm extending substantially radially, the engagement surface contacting the outer periphery of the auxiliary spring (22) and extending substantially radially.
7. A belt winder according to claim 6, wherein the belt winder is adapted to be moved axially towards a friction surface (46) fixed to the housing by pressure applied from the periphery of the belt winder (22). (8) A friction disk (44) mounted so as to be freely rotatable between the engagement surface of the second arm of the engagement member (40) and the friction surface (46) fixed to the housing. ) is arranged, the disk cooperating drivingly with the engagement surface on its side facing said engagement surface, and on its side facing said friction surface (46), said friction surface (46). 8. A belt winder according to claim 7, further comprising a friction surface cooperating with the belt winder. (9) The engagement member (40) is pressed radially outward to the operating position by a force applied from the outer periphery of the auxiliary spring (22), and in this position surrounds the ratchet wheel (24). 5. The belt retractor according to claim 4, wherein the belt retractor is adapted to frictionally connect with a friction surface fixed to the housing. (10) From claim 1, wherein a plurality of engaging members (40) distributed on one circular surface of the ratchet wheel (24) are mounted on a wire ring (42) held on the ratchet wheel. A belt winder as described in any one of the headings up to 9. (11) The auxiliary spring (22) is reinforced in the part of its outer layer(s), and before the auxiliary spring (22) is tensioned and its outer periphery itself separates from the engagement member, the auxiliary spring (22) 11. A belt winder according to claim 1, wherein the tensioning of the belt winder 22) causes the windings arranged inwardly of said part to contract. 12. Belt winder according to claim 11, characterized in that the reinforcement of the auxiliary spring (22) in the part of the outer layer(s) takes place by inserting a leaf spring.